O'Brien expressed excitement about teaming up again with the company that sponsored his "Legally Prohibited From Being Funny on Television Tour" this past summer.

"I admire them," O'Brien said. "They just work with great people like Jerry Seinfeld, Tiny Fey and Martin Scorsese. They let them do what they want."

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The new AmEx ad featuring Conan will start airing today, in order to coincide with the premiere of "Conan." In it, Conan - a man famously obsessed with details - scours the world looking for the best materials to make the curtains for the set on his new show. He ends up in India and proceeds to use a loom to weave fabric, stomps on flowers to create the dye, and chats up local cleaning ladies while he dies the curtains.

O'Brien was reportedly paid $1 million for the spot, but when asked about compensation, he offered up - what else? - a joke.